Additional information: I was actually able to upload this yesterday with Application Loader, but after submitting through iTunes Connect, I received the following response from Apple today:
"Invalid UIDeviceFamily - The Info.plist of Apple Watch application 'NASA_POD.app/PlugIns/com.apod.watchkitextension.appex/NASA_PODWatchKitApp.app' contains an invalid UIDeviceFamily value of '1'."
I made an update today, and tried to upload again through Application Loader, and received the error message in Comment 3.